ON THE SPINNING MECHANISM OF POLYVINYL ALCOHOL SOLUTION:(I). THE EFFECT OF EMERGING VELOCITY OF FILAMENT FROM COAGULATING BATH ON TENACITY AND ELONGATION OF DRAWN FILAMENT

After a polyvinyl alcohol filament was emerged from coagulating bath, it was drawn in wet state, in hot air, or in wet state and then in hot air. The maximum draw ratio and the maximum tenacity were obtained when the filament was drawn in hot air, or in wet state and then in hot air. The relation between tenacity ratio of drawn filament against the undrawn and the draw ratio is expressed by a straight line which passes through the original point, independent of the various drawing methods used. In filament which emerged from the coagulating bath at relatively lower velocity, the slope of the line is about 0.8. The relation between breaking tenacity and elongation is also expressed by a single curve independent of the drawing methods. As the emerging velocity is increased, tenacity at the same elongation and the maximum tenacity decrease.